Canon G15 vs Nikon P7700 Noise RAW

To compare RAW noise levels under real-life conditions, I shot this scene with the Canon PowerShot G15 and the Nikon Coolpix P7700 within a few moments of each other using their RAW modes at each of their ISO sensitivity settings.

The zoom on both cameras was set to their maximum wide angles, 6.1mm on the G15 and 6mm on the P7700, providing an approximately equivalent field of view.

Image stabilisation was disabled for this tripod-mounted test and all other settings were left on the defaults.

The image above was taken with the Canon PowerShot G15. The camera was set to Aperture priority mode with the aperture set to f2 and the sensitivity was set to 80 ISO. The PowerShot G15 metered an exposure of 1 second at f2, with exposure compensation set to +1EV to produce a sufficiently bright image with a histogram in the middle of the chart. With exposure compensation silmilarly set on the Coolpix P7700 it metered 1.3S at f2.

I processed both sets of files in Adobe Camera RAW using identical settings: Sharpening at 70 / 0.5 / 36 / 10, Luminance and Colour Noise Reduction both set to zero, and the Process to 2012 with the Adobe Standard profile. To further reduce any distracting visual differences between the crops I also set custom white balance to 4500K and tint to 0. These settings were chosen to reveal the differences in sensor quality and isolate them from in-camera processing. The high degree of sharpening with a small radius enhances the finest details without causing undesirable artefacts, while the zero noise reduction unveils what's really going on behind the scenes - as such the visible noise levels at higher ISOs will be much greater than you're used to seeing in many of my comparisons, but again it's an approach that's designed to show the actual detail that's being recorded before you start work on processing and cleaning it up if desired.

As with the RAW outdoor crops, these high ISO noise crops from the PowerShot G15 and Coolpix P7700 are very revealing and tell us more about the quality and noise performance of these two sensors than the JPEG results on their own reveal. In terms of noise, there's actually not as much of a difference between these two cameras as the JPEG results might lead you to expect. In fact I'd go so far as to say there's really nothing in it throughout the ISO range, right the way up to the Coolpix P7700's 6400 ISO maximum.

What you can see is that the PowerShot G15 crops are generally softer. Whatever the reason for that, when the noise suppression algorithms go to work it means there's greater detail loss in the G15 crops. I expect that's one of the reasons for the marked drop in quality of the in-camera JPEGs at the 800 ISO sensitivity setting.

What does this mean for enthusiasts attempting to get a quality boost by shooting RAW? At the low ISO sensitivities it should be possible to improve on the in-camera JPEG processing to produce a result with slightly more detail and crisper edges. But as you move up the sensitivity scale, it's going to become more difficult to retain image detail while dealing with the noise. In itself the noise isn't really the problem, it's the slightly soft rendition characteristic of the G15's lens and sensor combination.